 		   tgt-prefix (str src-prefix "." split-key)
 		   tgt-extra-pairs src-extra-pairs ;;(concat src-extra-pairs [[split-key "*"]])
 		   dummy (trace "SPLIT tgt-extra-pairs" tgt-extra-pairs)
-		   tgt-data-tuple [tgt-metamodel tgt-prefix tgt-extra-pairs]]
+		   tgt-data-tuple [tgt-metamodel tgt-prefix tgt-extra-pairs :split]]
 	       ;; register it with the global metamodel
 	       (trace "SPLIT DATA SRC  " src-data-tuple)
 	       (insert *metamodel* tgt-metamodel)

					  (insert *metamodel* count-model)
					  (insert tgt-metamodel [count-model extra-pairs])
					  (connect src-model count-model))))]
		 [tgt-metamodel new-prefix extra-pairs])))])))

(defn sum [sum-key]
  (fn [[metadata-fn data-fn]]

					  (insert *metamodel* sum-model)
					  (insert tgt-metamodel [sum-model extra-pairs])
					  (connect src-model sum-model))))]
		 [tgt-metamodel new-prefix extra-pairs :sum])))])))

(defn split-key-value [key]
  (str "split(" (or key "") ")"))
